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AC Dedicated Line

Hello guys
I will run three (3) dedicated AC power lines: one for my stereo system (power amp, preamp, DAC, etc) and two for my stereo subwoofers (one line for each one).

These three circuits will be connected directly to the main AC board of the Electrical Comany wich provides me the service right at my door.

They will all share the same ground cable, wich I will connect to a dedicated ground bar, but I would like your opinion about sharing the "same neutral line" on these circuits. Could it affect the sound quality? 

If I have to send three different neutral cables, one for each circuit, I will need more cable to run through the house and it will be more expensive and complicated.

Please I would appreciate responses with real experiences. I don't want to start a technical discussion. I know at the end, in the main board, they all will share the same neutral line, so electrically it should be the same, but in this crazy audio world who knows for sure if soundwise it will be the same....

PS: by the way, I will run 4 or 6 mm2 cables (I guess about 11 to 9 AWG on the US scale). Here in Argentina we measure cables by square millimitres.
plga
rbstehno
1,407 posts
 
I don’t agree that running 1 - 20amp circuit is all you need. Without knowing all the equipment you have today or you will get in the future, why only put in 1 circuit when running wire for 2 or more circuits isn’t that much more?
I agree, you need to see how much power you are pulling when everything gets powered up. To do this, have an electrician place their meter around the wire in the box to see the actual amps you are pulling. I did this 20 years ago and you would be surprised to see how many actual amps you draw. 
On top of that, you want to give yourself some headroom, meaning if you are pulling 12 -15 amps, I would go with multiple dedicated circuits.
I built my last 2 houses with dedicated listening rooms and each room I had them pull 4 dedicated 20 amp circuits, I think it cost me $450 for these. Better to do it before the drywall goes up or it gets much more expensive
plga OP
184 posts
 
Thank you guys!

Im sorry, may be I wasn't clear enough.

The main power of my home is triphasic and, from the main board, all the monophasic circuits are connected to somehow balance each phase with similar current.

All the circuits share the same neutral. Its been running ok since 10 years and the electricity bill is cheaper here with triphasic. 

I first thought that connecting each of the three circuits to a different phase would provide better results as each one would be better isolated from the rest. Nevertheless, I think I find millercarbon's advice very useful and I will make it simple and just run one circuit with dedicated ground for the whole system and the subs.

PS: I already have two budget power conditioners (AC filter and a DC Blocker) and they are doing a great job, but at nights, when the power is cleaner, the sound is just so incredible that I want to give it a shot and try this dedicated circuit to see if it makes a difference. Many people claim that it helps a lot. 
plga OP
184 posts
 
Im sorry Rbstehno, I didnt see your post as we wrote it at the same time. 

I just measured last week my system and the subs consumption and, even at loud volume, more than what I hear normally, my system didnt consumed more than 1 amp and neither did the subs.

At first I thought the meter was wrong, but then I remembered that the DC Blocker had also a meter and I saw it measured very similar to the external meter.

I think the low consumption must be because my power amp is class D, the same as the subs, and of course the preamp and the DAC dont consume much. 

So, in my case, 10 Amps should be more than enough. Nevertheless, if I decide to run just one circuit, I will go with a 10 AWG wire and a 32 amp breaker. 
elliottbnewcombjr
5,252 posts
 
Ignoring science, just instinct,

I keep my amp and preamp on one dedicated circuit, and all the source equipment powered from any household outlet on any circuit without equipment that surges on/off like refrigerators, fans, compressors ...


three_easy_payments's avatar
three_easy_payments
2,097 posts
 
I’ve often wondered why so many folks think they need a 20A circuit for their 2-channel audio systems. I have a 120W Class AB tube amp, tube preamp, tube phono pre, streamer/DAC, and TT. I’ve measured my power and amp draw with everything running at once and it’s about 400watts and 3.8amps. What are all you guys running that requires a 20amp circuit? 15amps seems like plenty to me. is there some hidden advantage of 20amp that I’m unaware of? I’m no electrical guru so perhaps I’m missing something obvious.
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